Pyranthrone-halogen complex addition compound and process of making the same



Patented Oct. 2, 1934 p 4 p 2 PYRANTHRONE-HALOGEN COMPLEX AD- BTION COMPOUND AND PROCESS OF IVEAKING THE SAME Joseph Deinet, Milwaukee, and David Katz, South Milwaukee, Wis, assignors to E. I. du Pont de Nemours 8; Company, Wilmington, Del., a corporation of Delaware No Drawing. Application October 15, 1932, Serial No. 637,986

24 Claims. (Cl. 260-451) This invention relates tonovel organic comarylainines are highly reactive toward halogen. pounds of the pyranthrone series and to a process In any event, they are more reactive toward haloof preparing the same. More particularly, this gen than pyranthrone. It seems that when susinvention deals with novel halogen-pyranthrone pended or dissolved in an inert organic liquid in addition-compounds which are useful for the the presence of pyranthrone and a halogenating preparation of novel halogenated pyranthrones. agent such as sulfuryl chloride or bromine, the

In copending application Ser. No. 637,985, by arylamine is attacked first and becomes highly one of us, is disclosed a new series of halogenated halogenated. In doing so, sulfur dioxide or hypyranthrones which are distinguished from the drobromic acid (as the case may be) is liberated l0 isomeric known pyranthrones by the fact that in nascent state. It appears that this nascent when condensed with alpha-amino-anthraquinreducing agent catalyzes the reaction between one, they give vat dyes which dye cotton in khaki the pyranthrone and the halogenating agent. Or to olive green to dark green shades. As disclosed againy reducing agent y function me e y in said ccpending application, it has been found to establish equilibrium between an intermediate 15 a requisite condition in the process of preparing complex v hr n -hal s n additi nmnsaid novel halogenated pyranthrone to conduct pou and its decomposition p In any the reaction so as to lead first to the preparation v t e py 'fi is q y COIlVerted i t a of an intermediate complex body involving pyranblack suspension mass which is insoluble in nithrone and halogen. This intermediate complex trobenzene. When viewed under the microscol 2o body, when decomposed by the aid of anhydrous i p en h f rm f dark viol n dl s having oxidizing or halogenating agents, leads to novel a green uoresc nc halggen-pyranthrones, This pyranthrone-halogen body is fairly stable The present invention concerns itself mainly at Ordinary temphlatules When maintained in its with these pyranthrone-halogen complex bodies, 0WD reaction mass Moisture, heat Contact 25 and with the process of preparing them. With all, however, de p it p y into It is an object of this invention to produce novel Dy and halogen- Alcohol 01 acetic acid pyrg nthyone-halogen addition-compounds which have a similar effect. Anhydrous oxidizing agents, are useful for the preparation of halogenated Such as strong hl rin ins n decompose it pyranth-l-Ones' into novel halogenated pyranthrones, probably 30 It is a f tl e object of our invention t isomeric with, but nevertheless distinct from vide a process for preparing these novel pyranknown -py e as more fully throne-halogen addition-compounds. cussed below- Y Other and further important objects of this in- The Constitution Of this novel body s 1 0 vention will appear as the description proceeds. known With Certaintyom its mode Of forma- I We have found that if pyranthrone is reacted tion and behavior We would d e t t i is a upon with halogenating agents in the presence of pleX addition-Compound 0f py anthrone and the certain catalyzers, as more fully set forth below, particular halogenating a t used, Such as sulnovel halogen addition compounds of pyranthrone y Chloride, bromine, u u monobromide 01' are produced which have the property of yielding y r c acid- But it does Seem to be well novel and useful halogen-pyranthrone comestablished that the additive molecules enter in pounds when reacted upon with anhydrous oxip t W molecules of halogenating dizing or halogenating agents. The requisite agent 130 e c 11101601116 0f p ra t one. It also catalyzers mentioned above are anhydrous,mild Seems fair y C r that t entering u es reducing agents, or substances capable of develop take a certain definite position in the pyraning such reducing agents by .reactingrwith certain throne structure, very likely in the meso carbon. 1 0

components of the reaction mixture. Thelatatoms. This assumption seems to explain the ter class comprises organic substances which are fact that when the addition-compound is treated readily susceptible to halogenation in anhydrous with an anhydrous oxidizing agent or a different medium by means of bromine or sulfuryl chloride. and stronger halogenating agent than the one In doing so, these substances liberate hydrobromic from which it was formed, it decomposes and acid or sulfur dioxide, respectively, which constiyields a novel mono-, di-, or tri-halogen pyrantute the mild reducing agents above noted. throne (depending on the particular halogenat- The simplestand most active representatives ing agent used), differing in properties from of this novel series of catalyzers are the arylknown halogen-pyranthrones of the correspondarnines, typified by aniline. As is well known, ing halogen content- This difference in proper- 119 orienting nature.

ties is best shown up by the shade of the vat dyestuff obtained when one of these novel halogenpyranthrones is condensed with alpha-aminoanthraquinone; as more fully set forth in copending application'by one of us, Ser. No. 637,987.

It will be understood from the preceding that our designation of these novel intermediates as pyranthronei halogen addition-compounds is merely a shorthand way of naming the cornpound obtained by reacting upon pyranthrone with a halogenating agent in the presence of a mild reducing agent or in the presence of an organic substance readily susceptible to halogenation. Similarly, the designation of said last mentioned substances as catalyz'ers is merely a convenient way of designating these compounds,

and should not be construed as limiting this in- It seems that all that is necessary of a particu-' lar organic substance to be suitable as a catalyzer' for the above purpose is that it be more readily halogenable with the particular halogen selected than pyranthrone, and that it be soluble in the particular suspending medium selected;

The quantity of catalyst required for the above purpose is very small. Indeed, it has been observed that where recovered ni-trobenzene is employed as a solvent, the trace of aniline present therein as an impurity is sufficient to exert the requisite catalytic effect. For this reason and in view of its low cost, recovered nitrobenzene makes an excellent suspending medium for the above'reaction, and requires no addedcatalyzer whatever.

ther solventsor suspended media may be employed, if desired, the limitations being first that it be anhydrous or capable of being dehydrated before use, and secondly that it be difficult of halogenation itself. Y The first limitation is necessary in view of the fact that our novel pyranthrone-halogen addition-compounds are unstable in the presence of moisture. The second limitation has as its object clearly to avoid waste of halogenating agent. As specific examples of suitablesolvents or suspending media may be mentioned nitrobenzene, dichlorobenzene, trichiorobenzene and tetrachlorethane.

As halcgenati-ngagent, any one capable of working in anhydrous solution may be used, but preferably it should not be a powerful oxidizing agent. Bromine, hydrobromic acid, sulfur monobromide and sulfuryl chloride are specific halogenating agents used by us with great success.

' If desired, well recognized halogen carriers or catalysts, such as iodine, may be added to speed up the reactioni These are to be distinguished 'from the special catalyzers mentioned in this specification. The effect of iodine is to'accelerate or speed up the reaction. The effect of aniline, phenol, sulfur dioxide, or the other catalyzers mentioned hereinis more of a directing or They determine the course of is substantially complete.

the reaction and the nature of the final product.- For specific distinction, where necessary hereinafter, we shall refer to the iodine type catalyst as a speed catalyst and to the aniline type as a directing catalyst.

Without limiting our invention to any particular procedure, the following examples, in which parts by weight are given, will serve to illustrate our preferred mode. of operation.

Example 1 parts of dry, amorphous pyranthrone are suspended in 600 parts of nitrobenzene containing 1 part or" aniline hydrochloride. 35 parts of bromine are then added. and the mass is stirred at Si -80 C. for about 18 hours. At this point the formation of the intermediate addition product The originally orange mass turns black, and when a sample is viewed under a microscope it appears to consist of dark violet needles having a green fluorescence.

The mass is now cooled to 20 C.;. parts of sulfurylchloride are added; and the mass is stirred at 20-22 for about 24 hours. perature is now raised to C.; held at this value for 3 hours; raised further to 115-116 0., and.

maintained at this point for. another 3 hours. During the latter stage the mass changes color again and becomes red. The mass is then cooled to room temperature and filtered; the filter cake is washed successively with nitrobenzol and: al-

cohol and dried.

The product thus obtained analyzes 23.2% Brand 3.6% Cl, and is very probably a mixture of dibromo-pyranthrorre and monobromo-monochloro-phyranthrone. 'ir'v'hen dry it is av scarlet powder, soluble in concentrated sulfuric acid with a reddish blue color, and in hot nitrobenzene with an orange color. It can be used directly as a vat dyestuff, and dyes cotton from a red-violet vat in bright orange to scarlet shades.

When condensed with alpha-amino-anthraquinone it gives a vat dyestufi dyeing cotton from a violet vat in. very strong and fast olive-green shades.

ErampZe 2 40 parts of dry, amorphous pyranthrone are suspended in 600 parts of nitrobenzene containing" A mixture of 35 parts of bromine and Bil-parts of thionyl chlo- 1 part of aniline hydrochloride.

ride is added and the mass is stirred at 20-22" C. for about 90' hours. The originally orange mass has by this time turned dark. To insure complete reaction, the temperature is raised to C;; 'maintained at this Valuefor 3 hours; further raised to 115 CL, and kept at this point for another 3 hoursu During the latter stage the mass brightens up again and turns orange-brown. The

mass is now cooled, and the product filtered oii,

washed and dried. r

The dry product is an orange-brown powder, dissolving inconcentrated su furic acid with a reddish-blue color. It may be used directly as a vat dyestufi, and dyes cotton from a violet vat The temin orange shades. When condensedwith alphaamino-anthraquinone it gives a vat dyestuii dyeing cotton from, a, violet vat in khaki shades, of good tinctorial strength and excellent fastness qualities; i The product of this exampleanalyzes 12.5% Br and 1.8 Cl, and-is very probably a novel monobromo-pyranthrone. In this example the formation of the intermediate additionproductandits oxidation by the thionyl chloridehaveibeen made to run to a certain extent concurrently. -This condition, however, is not absolutely necessary, for it is possible to'proceed first'with the prep'arationofv a distinct intermediate addition-productas in Example 1, andth'en toreact upon-the mass with thionyl chlorideto produce-tithe novel monobromo-pyofaniline hydr chloride and OA parts ofiodine are add .GOQpa-rts of sulfuryl chloride are then introducedfand the mass is stirred {$229239 0. for 2elhour's. A blacl; intermediate addition-com? pound, is formed, of Exampl'e 1 Example 5 7 40 parts of dry, amorphous phyranthrone 'are suspended in 600 partsof 'nitrobenzene, and 1 part' of aniline hydrochloride plus 0.4 parts of iodineare added. A stream'of hydrob'romic'acid gas, asobtained by reacting-with sulfuric acid upon sodium bromide, is now passed in, until 36 parts have been absorbedm'lhe mass isstirred at room temperature for hours. The initially orange mass turns black, 'indicating'the formation of the intermediate complex addition-compound. The latter, when examined, appears similar to the addition-compound obtained in Examplel. i Ew pl eoparts of dry, amorphous pyranthrone are suspendedinSOO parts of nitrobenzene and 1 part of anilinehydrochloride plus 0.4 parts of iodine are added. 60 parts of sulfuryl' chloride are now added, the mass is heated to '55-60 C., and stirred at this temperature for 18 hours. A black intermediate addition-compound is formed which appears to be substantially identical with or very'similar to the product obtained in Example 4.

Example 7 intermediate addition-compound formed appears to be identical with that of Example 1.

' Example 8 The procedure is the same as in Example 2,

except that in lieu of 1 part of aniline hydrochloride, 1 part of phenol is used. The black intermediate addition-compound obtained appears to be identical with that of Example 2.

Example 9 parts of dry, amorphous pyranthrone are suspended in 600 parts of nitrobenzene. A stream of sulfur dioxide, as obtained by reacting with sulfuric acid upon sodium bisulfite, is slowly passed into the mass until no longer absorbed by re e l -i i i e tha the .nitrobenzene. 35 parts of bromine are now added; the ,mass is heated to about -60 C. and stirred at this temperature for several hours. An intermediate black compound is formed which appears to be identical with that obtained in Examplel.

I r General I *If'in'an'y of the aboveexamples, the aniline hydrochloride is replaced by any of the catalyzers mentioned above, such as 0-, m-, orp-toluidine; alphaor beta-naphthylamine, the hydrochloride or other salt of-any of these; phenol, cresol, naphthol, hexalin or'salts of these such as the alkali-metal salts; toluene, solvent'naphtha, ac tone,or mixtures of any two or more of these, the results obtainedare thesame'g It'will be understood that ourinvention is not limited to the precise procedure above set forth. Thus, although we have preferred touse the same quantities of pyranthrone and bromine or pyranthrone and sulfuryl chloride ineach example', for the sake of facilitating comparative study, thefproportio-n'smay be varied within: wide limits; The; natural lower limit, for complete con version of the pyranthrone', is two mols'of the halogenating agentper mol of pyranthrone. An excess-of halogenating agent, however, does no harm and isindeed beneficial- Best resultsare obtained by using-4 to 5 mols of halogenating agentper mol of pyranthrone. Similarly, the

temperature of the-reaction may be variedconsiderably. 20 to C. makes an ideal working range. v v v Many other variations andmodification s are possible in our preferred mode of procedure, without departing from the spirit of this invention,

as defined by the subjoined claims.

In the claims below it should be understood that by the terms a catalytic proportion, we are referring to a small quantity of the substance being discussedffar below stoichiometric as compared tothe quantity of pyranthrone being halogenated, and being ofthe order of magnitude in which catalysts are generally e1nployed,"which, as is well known, generally rangesfrom a trace to a few percent by weight of thesubstancebeing catalyzed. i

We claim; f

1. The process of producinga pyranthronehalogen addition-compound which comprises reactin with a, halogenating agent uponpyr'anthronein the presence of a catalytic proportion of a mild, anhydrous reducing agent.

2. The process of producing a ,pyranthronehalogen addition-compound which comprises reacting with a halogenating agent upon pyranthrone in the presence of a nascent anhydrous reducing agent.

3. The process of producing a pyranthronehalogen addition-compound which comprises reacting with a halogenating agent. upon pyranthrone in the presence of an organic compound which is readily susceptible to halogenation.

4. The process of producing a pyranthronehalogen addition-compound which comprises reacting with sulfuryl chloride upon pyranthrone in the presence of sulfur dioxide.

5. The process of producing a pyranthronehalogen addition-compound which comprises reacting with sulfuryl chloride upon pyranthrone in the presence of an organic compound which is readily susceptible to chlorination by means of sulfuryl chloride.

6. The process of producing a pyranthronebromine addition-compound, which comprises reacting with bromine upon pyranthrone in the presence of an initial quantity of hydrobromic acid.

7. The process of producing a pyranthronebromine addition-compound, which comprises reacting with bromine upon pyranthrone in the presence of an organic compound which is readily susceptible to bromination.

8. The process of producing a pyranthronehalogen addition-compound which comprises reacting witha halogenating agent upon pyranthrone in the presence of a directing catalyst and a speed catalyst.

9. The process of producing a pyranthronehalogen addition-compound which comprises reacting with a halogenating agent upon pyranthrone in the presence of a catalytic proportion of a mild anhydrous reducing agent and a speed catalyst.

10. The process of producing a pyranthronehalogen addition-compoundwhich comprises reacting with a halogenating agent upon p-yranthrone in the presence of an organic compound which is readily susceptible to halogenation and in the presence of a speedcatalyst.

11. The process of producing a pyranthronehalogen addition-compound which comprises rea acting with a halogenating agent upon pyranthrone in an anhydrous organic liquid medium and in the presence of a readilyhydrogenable organic compound selected from the group consisting of aromatic amines, hydrocarbons, phenols,

v cyclic alcohols, aliphatic ketones, and salts of any halogen addition-compound which comprises reacting with a halogenating agent upon pyranthrone in an anhydrous organic liquid medium and in the presence of a compound selected from the group consisting of phenol, cresol, hexalin,

. alpha-naphthol, and salts of these.

16. A process as in claim 15, said halogenating agent being selected from the group'consisting of sulfuryl chloride and bromine.

17. The process of producing a pyranthronehalogen addition-compound which comprises reacting with a halogenatmg agent upon pyranthrone in the presence of nascent hydrobromic acid.

18. The process of producing a pyranthronebromine addition-compound which comprises reacting with bromine upon pyranthrone in the presence of nascent hydrobro-mic acid.

19. The process of producinga pyranthronehalogen addition-compound which comprises reacting with a halogenating agent upon pyranthrone in the presence of nascent sulfur dioxide.

20. A process for producing a pyranthronesulfuryl chloride addition-compound which comprises reacting 1 mol of pyranthrone'with 4 to 5 mols of sulfuryl chloride in an inert organic medium and at a temperature between 20 and 60 C. in the presence of sulfur dioxide.

21. A process for producing a pyranthrone-sulfuryl chloride addition-compound-which comprises reacting 1 mol of pyranthrone with 4 to 5 mols of sulfuryl chloride in an inert organic medium and at a temperature between 20 and 60 C. in the presence of sulfur dioxide in nascent state.

22. A process for producing a pyranthronebromine addition-compound which comprises reacting 1 mol of pyranthrone with 4 to 5 mols of bromine in an inert organic medium and a temperature of 2 to 60 C. in the presence of a catalytic proportion of sulfur dioxide.

23. A process for producing a pyranthronebromine addition-compound which comprises reacting l mol of pyranthrone with 4 to mols of bromine in an inert organic medium and a temperature of to C. in the presence of nascent hydrobromic acid.

24. The process which comprises reacting with a halogenating agent upon a suspension of pyranthrone in nitrobenzene containing further a catalytic quantity of a readily halogenable organic compound, until the initially orange colored pyranthrone has been substantially completely converted into a black bodywhich under the microscope presents the appearance of dark violet needles having a green fluorescence.

JOSEPI-I DEINET.

DAVID KATZ. 

